Recliner chairs and other reclining seating units have proven to be popular with consumers. These seating units typically move from an upright position, in which the backrest is generally upright, to one or more reclined positions, in which the backrest pivots to be less upright. The movement of the seating unit between the upright and reclined positions is typically controlled by a pair of matching reclining mechanisms that are attached to the seat, backrest and base of the chair.
One particularly popular reclining chair is the so-called “rocker-recliner,” which can, when in the upright position, rock with a forward and rearward motion similar to that of a traditional rocking chair. A typical rocker recliner, one of which is illustrated in U.S. Pat. No. 4,519,647 to Rogers, includes an arcuate rocker cam that is attached with the lower portion of each mechanism, with the lower convex surface of the rocker cam contacting a level bearing surface of the base. Also, a spring assembly is mounted to the base of the chair and to each rocker cam. Each spring assembly includes two quite stiff, vertically-oriented helical springs attached to mounting brackets that are in turn fixed to the base and to the rocker cam. When the chair is in its upright position and is unoccupied, the seat, backrest and reclining mechanisms reside above the base, the rocker springs are deflected only along their longitudinal axes, and the rocker cams rest on a level portion of the base. When an occupant sits on the chair and applies a forwardly- or rearwardly-directed force to the seat or backrest, the seat and backrest move relative to the base. The path of movement is defined by the convex shape of the rocker cams as they rock on the level bearing surface of the base, with the result that the seat and backrest simulate the rocking motion of a rocking chair. During the rocking movement, the rocker springs deflect such that their top portions bend away from their longitudinal axes as the chair rocks forward and back. The deflection in the springs urges the springs (and, in turn, the seat and backrest) to return to their original positions as the chair returns to and through the upright position. In this manner, the chair is capable of providing a controlled rocking motion when in the upright position.
Many, if not all, chairs of this design include some type of safety feature, such as an extendable foot, that prevents rocking when the chair is in a reclined position. For example, U.S. Pat. No. 6,000,754 to Lawson discloses a rocker lock that is pivotally interconnected with the rear portion of the reclining mechanism and with the base of the chair. More specifically, the rocker lock includes three separate pivotally interconnected links mounted to the base and to the reclining mechanism. A bracket is mounted to and extends above the base. A slotted link is pivotally and slidably attached to the bracket via a pin on the bracket. A support link, to which a roller is attached, is pivotally interconnected with the forward end of the slotted link and with the reclining mechanism. A control link is pivotally interconnected with the support link and to the reclining mechanism. In the upright position, as the chair rocks, the slotted link moves forwardly and rearwardly relative to the mounting bracket, as the pin on the mounting bracket is free to slide within the slot of the slotted link as it moves. As the chair moves to an intermediate reclined position (often termed the “TV position”), movement of the reclining mechanism causes the control link to drive the roller on the support link downwardly into contact with a plate attached to the base. The slotted link is forced rearwardly so that the pin of the mounting bracket is lodged against the front edge of the slot. This placement of the wheel and the pin in the slot prevents the chair from rocking.
This locking mechanism can have some shortcomings. Because the slotted link slides on the pin of the mounting bracket during the rocking motion, in some instances the occupant of the chair can rock forward sufficiently that the rear end of the slot strikes the pin, thereby giving a jolt to the occupant. Also, because of the configuration of the locking mechanism, if the occupant is rocking forward when releasing the chair to a reclined position, in some instances the chair can “catch” and impede reclining movement. One locking mechanism that proposes to overcome some of these shortcomings is discussed in U.S. patent application Ser. No. 10/982,108, filed Nov. 4, 2004 and entitled Rocking-Reclining Seating Unit with Motion Lock, the disclosure of which is hereby incorporated herein in its entirety. Nevertheless, it may be desirable to provide additional configurations for motion locking mechanisms that can remove cost and/or labor from the manufacturing process and that can improve performance.